I spent about 10 days climbing in Chamonix, during late June of 1998.
Chamonix is a spectacular place to climb snow, rock, ice, or hard
mixed routes. We came mainly to climb rock routes many of which were
not in condition yet, and many of which were somewhat over our heads.
We stayed at the Gite Chamoniard Volant, which is a nice place to
stay: lots of climbers, nice manager, cheap (66F/night), showers,
kitchen, etc. Camping is also an option, but it usually puts you a bit
out of town, which you may or may want. Despite my expectations,
Cham is not nearly as bad as I thought it would be. Yes, it is quite
developed, but it is easy to get away from it all, and people are
relatively friendly, you can live for pretty cheap, and the climbing
is uniformly fantastic (the Aguilles are world class granite). Below
is a summary of some of our activities there.

Alpine climbs (1998)

We did a 3 day trip up to the Col du Midi. Rather than staying in the
Cosmiques hut, which is expensive (I believe nearly 200F per night,
for half board) and reportedly crowded, we just brought bivy sacks,
and stayed out on rocks below Gros Rognon. This enabled us to get a bit
acclimatized and beat the cable-car day-trippers to the base of
climbs. We did 3 climbs.

Pt. Lachenal, Contamine Route

On day one (we didn't get up to the glacier until mid-afternoon) we
climbed the first 5 pitches of this route, to the base of the 5.10
cracks, at which point it started getting dark, so we rapped off. The
first pitch was probably hardest, due to the somewhat polished nature
of the rock. There's some route latitude, but mostly the route is
pretty obvious. 3 hours up and 1+ hour down.

Pyramid Du Tacul, E Ridge

This is a 9 pitch route, with no spots harder than 5.8 and a
rappel descent. It affords fantastic views of climbs on the NE face
of Mont Blanc du Tacul, which was one of the reasons we climbed it (to
scope out the Gervasutti pillar, a 25+ pitch route on the NE Face).
Again, the route finding is pretty obvious, and the rock is fantastic,
consisting of superb, coarse-grained granite, and lots of hand-sized
cracks. The route is descended via about 7 rappels. Be careful (move
quickly) at the base of the climb, as the next morning we saw a
massive serac avalanche wipe out our tracks. 5+ hours up and 3+ hours
down.

Mont Blanc Du Tacul, Regular Route

We decided that the Gervasutti Pillar was probably a bit over our
heads (climbing that was supposed to be about 5.7 was feeling more
like 5.8, which is probably due to the altitude; the top of the pillar
still looked a bit snow/icy) so we decided to just do the regular
route on this peak. This is a straightforward route, with some
sections of moderate snow and a couple of shrund problems. This was
also my first exposure to the legendary Chamonix crowds, which can
pose real hazards at bottlenecks (the short mixed section at the top,
and the shrund crossings on the descent). We had great conditions and
made good time, even with an hour delay at one shrund crossing. 5
hours round trip.

Rack and other Considerations

Since lots of the climbs here require rap descents, double ropes are
pretty much mandatory. We used 2x9mm ropes, although 2x8 would work
too. I saw some people using a long (100m) 8mm rope, which seems like
a good idea because there is no knot to get hung up, although a bit
clunky for the glacier walking.

We took a medium rack on the rock climbs, consisting of about cams
from #2 TCU to a #2 Friend, 4 of the larger hexes, 1.5 sets of
stoppers, and about a dozen slings (from quickdraw length to double
length).

We didn't bring any ice gear, as we weren't planning any mixed/ice
routes, but if that's your game, there's heaps of it around.

We used bivy sacks and had good weather. This did mean that we needed
to carry sleeping bags and a stove to melt snow, although the
cable-car takes lots of the sting out of this aspect. Supposedly
camping below the Aguille du Midi is illegal, but bivying is ok. The
difference is the bivying means that you take down your tent by
sunup. However, we saw at least 4 tents in permanent residence out on
the glacier.

Don't be fooled by the ease of access: this is a dangerous place.
Many of the bases of the climbs are threatened by serac falls from
higher up, and this isn't always obvious. It's the best policy not to
muck around at the base for too long. And don't follow the French
example of safe glacier travel. 80% of the parties we saw kept only
about 2 meters of rope between the members. This "short-roping" might
be ok for the steeper snow/ice slopes, but doesn't seem so wise when a
big crevasse opens up.

Hazy recollection: We climbed the Regular route (? I'll look up the
details later) on Dent du Requin. The route wanders up weaknesses
(left, right, then left towards summit) on the face. We were hit by a
heavy mist, and went too far right, eventually getting onto the ridge,
which turned into hard climbing. We diagonal rapped at least 2 full
ropelengths back down and left to get back on route. At this point
there was some of the harder (5.7 or so) climbing, before things eased
up near the summit. Getting down took a bit of downclimbing, and then
3 full length (more?) raps to the glacier, which we cruised back to
the Requin hut. We motored down the Mer de' Glace and made the last
train back to town. About 2 hours to start of climb, 6 hours on climb
(summit around 1pm), 2+ hours back to hut.

I also did a nice scramble on the other side of the valley and a bit of
bouldering Col d' Montet.

Sport Climbing

We spent more time sport climbing (there's a decent crag down valley
called Gaillands, although it's really polished) than I would have liked.
You don't go to Cham to do sport climbs, especially when the weather
is good. Oh well. Long story...

Bouldering

The best bouldering is found at Col d' Montet. Great setting, pretty
easy access from Cham (hitching is good, the train is easy), and
wonderful problems. Lots of mutants pulling crazy moves.